Low
S.28 on Vaillant Combi Compact 242EB

Your boiler is temporarily pausing the burner to prevent it from switching on and off too frequently while heating your water.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Hot water burner anti-cycling time

DIY fix possible

Wait for 10 to 15 minutes for the anti-cycle timer to finishEnsure hot water taps are fully turned offCheck that the boiler pressure is between 1 and 1.5 bar on the gauge

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Related fault codes

S.08View →S.27View →S.53View →

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